My 14 yr old son recently moved up to the men's sized pants and he wears two inches smaller in the waist than hubby. They also wear the same style of pants-Wrangler carpenter pants.

Hubby called this morning to tell me that he was feeling particulary trim after having been on a backpacking trip over the weekend and then he went to put on his pants and they were way too tight!!!
He was like - what the heck is going on? After he took them off, he figured out that they were our sons pants that I had put in his closet by mistake